This invention relates to apparatus for accelerating the emptying of railroad hopper cars and the like, such as are commonly used to transport coal, ore and similar materials.
Railroad hopper cars are commonly equipped with sloping bottoms and closure gates beneath them, with the gates being opened to permit gravity-influenced discharge of the contents of the car when so desired. In spite of the provision of the sloping car bottoms, the material to be discharged, whether it be coal, ore, or other similar material, often does not flow freely and continuously under the influence of gravity alone, but tends to bridge over the discharge openings from time to time, requiring considerable manual labor to free it and to complete emptying of the car.
In the past, various forms of old mechanical apparatus have been provided for accelerating the emptying of railroad hopper cars and the like and, thus, supplementing or reducing the amount of manual labor required to augment the aforenoted gravity-influenced discharge of material from such hopper cars.
U.S. Pat. No. 2,504,789 shows and describes an extremely mechanically complex, and hence quite expensive, form of such prior-art apparatus which has been manufactured and sold by Hewitt-Robins, Inc. since the early 1950s. While this particular form of prior-art apparatus has provided satisfactory results in accelerating the emptying of railroad hopper cars, it has the disadvantage of requiring a costly overhead structure and a crane or hoist to move it about with respect to the hopper cars. This form of apparatus is commonly referred to as an "over-the-track car shaker".
In an apparent attempt to reduce equipment cost when compared to the just-described form of prior-art apparatus, Hewitt-Robins, Inc. has also provided a later form of prior-art apparatus, such as that shown and described in its Bulletin No. 187a-5-G-766, which bears a 1963 claim of copyright. This later prior-art form of apparatus eliminates the aforenoted overhead structure and crane or hoist, and comprises frame means that are mountable through base means to a pair of generally-horizontally-spaced apart rails upon which the wheels of a railroad hopper car can be supported. The frame means is mounted next to one side of the rails and has connected to it, via a parallelogram linkage, an excitor means that is movable by a hydraulic fluid-cylinder motor into and out of contact with one vertical side of the hopper car. This prior-art form of apparatus is commonly referred to as "trackside car shaker" and its excitor means comprises a single hydraulic motor that is mounted to plate means, one face of which contacts the one vertical side of the hopper car and the other face of which is connected by vibration isolating springs to the aforenoted parallelogram linkage.
While the latter one of the two aforedescribed forms of prior-art apparatus offers an equipment requirement reduction over the former, it usually does not equal its performance in accelerating the emptying of railroad hopper cars and the like.
The present invention is directed toward providing a novel apparatus for accelerating the emptying of railroad hopper cars and the like, which is somewhat similar to the latter one of the two aforedescribed forms of prior-art apparatus, but which offers yet a further reduction in equipment required, while improving upon the performance of such a "trackside car shaker".